Interesting. Well it all makes sense. I'm trying to setup a routine for our corporation to regularly wipe our old hard drives before dumping and donating them. It's fairly sensitive data in that if our competitors got a hold of it, it would probably put us out of business. Seems that just the simple DoD standard should suffice though. Thanks for all your responses. -----Original Message----- From: Simple Nomad [mailto:thegnome@xxxxxxxx] Sent: Thursday, July 21, 2005 3:07 PM To: bugtraq@xxxxxxxxxxxxxxxxx Cc: Jared Johnson; focus-ms@xxxxxxxxxxxxxxxxx Subject: Re: Peter Gutmann data deletion theaory? On Wednesday 20 July 2005 18:48, Jared Johnson wrote: > Data overwritten once or twice <snip> The quote is from 1996. I spoke with Guttman about this at AusCERT a few years ago and even *he* doesn't believe it anymore. Drive technology has changed substantially since then. The main areas where criminals get caught with bad stuff on their drives by forensics people is from 1) not knowing where the data is being written to (browser cache, swap file, etc) 2) not doing any overwrite of the data as a part of deletion, and 3) not taking into consideration such items as file slack. Drives that do caching and file systems that do journaling also may be a factor. That being said, 3 wipes are "good enough for government work". DoD 5220.22-M chapter 8 subsection 306 in the Cleaing and Sanitization Matrix shows under the Magentic Disk section that to properly sanitize a non-removable rigid drive, that the choices of degaussing, destruction of the drive, or a 3 pass wipe are acceptible methods for disk sanitation. Note that the 3 pass wipe method is NOT acceptable for drives that contained Top Secret information - so unless the drive contained Top Secret material, you're covered. It should be noted that this issue has been done to death on bugtraq several times. -- # Simple Nomad, C²ISSP -- thegnome@xxxxxxxx # # C1B1 E749 25DF 867C 36D4 1E14 247A A4BD 6838 F11D # # http://www.nmrc.org/~thegnome/ #
